Bass, low end, subs, bottom... the list goes on. Whatever you call it, low frequency production is something I'm asked about all the time. In this extended tutorial I'll attempt to pack a super dose of bass handling techniques into one tutorial.
We'll take a look at everything from composition techniques to production and processing tips. Of course everyone has their favourite way of treating bass and you may have yours but this tutorial should help improve your technique and give you some new ideas.
Step 1: Sound Selection
It all starts with the sort of sounds you select for your project. I can't count the amount of times I've been given projects and told, "The kick just won't fit with the bass." Or "Some of my bass notes are too loud or quiet in the mix." Most of the time these frustrating issues are down to a simple case of bad combinations.
Of course these symptoms can be a sign something else is going wrong in your mix but a good way to start attacking the problem is taking a closer look at your basic elements. Before you start applying any production techniques or processing to your signals, you may be able to improve your low end mix by simply changing the sounds your using.
As we are interested in our low end elements here likely suspects are the kick drum you maybe using and any bass parts. The main pitfall most people fall into is using a kick and bass part that share similar frequencies. For example using a very deep kick and bass part that play at the same time will create some serious problems and ultimately rob your mix of intelligibility.
A good practice here is to choose sounds thats occupy specific fundamental frequencies. For instance using a kick drum that lives around 100hz and above will marry very nicely with a deeper bass sounds that occupies sub bass frequencies of 90hz and below. Reversing this example would also work, using a higher bass sound and sub rich kick.
Get things right here and you may find that you don't need to do much more work to get things into shape. There are situations where you need to use low end elements that share the same frequencies though, so the following stages will delve into some techniques that deal with just that.
Step 2: It's All in the Groove
One excellent way of combining a number of elements that contain the same low end frequency is to use some clever programming. You may not associate sequencing and playing style with managing your low end mix but it can be one of your most valuable tools here.
By simply programming your bass line around your kick drum pattern you can avoid the two clashing. This will in turn allow the two to breathe and give them space to fully develop. Again, get things in to the right 'slot's here and you may not have to do much else to get your low end parts to work together.
So let's say for arguments sake you want to use kick drum and bass sounds that share common frequencies and you also wan them playing at the same time. Let's face it most of our tracks will contain combinations like this and although this will require a little more work to get right, the following steps should give you a few alternative courses of action.
Step 3: Side Chaining
One of the most effective ways to marry two low frequency sounds is the use of side chaining or 'ducking'. This process includes using a compressor with a key input to reduce one of your signals in volume when the other is present.
The most obvious use for this technique is applying the ducking effect to a bass line (or other low frequency instrument) and then using your kick drum as the trigger for the gain reduction. This simple effect not only allows both sounds to be heard clearly in your mix but it can also introduce a pleasing 'groove' to your parts. This is induced my the link created between the two sounds.
Although the effect produced by side chaining can be compared to clever programming that omits bass notes when our kick drum is playing, you have to remember this process is fully variable and can supply everything from a subtle dip in volume all the way through to near complete removal of a sound.
If you are having an issue with a confused low end mix and my first few suggestions aren't working for you, try some simple side chaining. It could just be the key to a clearer tighter mix. If your still not satisfied, keep reading!
Step 4: Surgical Filters
If you find that the combination of bass heavy signals you are using still aren't playing nicely and you really don't want to change them you may have to turn to some good old signal processing. Our first stop is the humble EQ.
We can use a combination of high and low pass filters to persuade our sounds to gel. Most equaliser plug-ins have these filters included and they are extremely dimple to use. By rolling off the subs from one element and the higher frequencies from another our treated sounds can be slotted together.
When using filtering in this way the crossover doesn't have to be exact, as long as the fundamental frequencies that are clashing are removed you should find that this allows the two sounds to exist in the same space.
Up until now we have only talked about removing parts of our sound to enhance our low end mix. In most cases this subtractive approach will work well but sometimes your instruments maybe perfectly married but lack depth and shine. If this is the case we can use our processors in a more additive manner.
Something as simple a low shelving EQ can add a whole new dimension to a bass part or alternatively try to add some low mids to your baselines, this will often add a whole new range of harmonics and make it more intelligible on a wider range of systems. As with most of these techniques, small, simple changes can go a long way.
Step 5: Multi-band Magic
Another way to control and enhance your bass parts is group processing. As soon as you feed your bass and percussion parts through the same group and apply any sort of dynamics processing something pretty special happens. The result is a unified, cohesive sound that should provide a good level of low end focus.
The only problem with this approach is that if we use a single band compressor to treat our grouped sounds every frequency will be affected, so even sounds in containing higher frequencies will be compressed and have their dynamic range reduced. As we are concentrating on only our low frequencies we'll need a specialised tool.
Multi-band compression is capable of homing in on specific frequencies and in this case we can apply as much or as little processing to just the lower range. This means if your entire drum group and bass line are all being compressed just the low frequencies can be processed while the rest of the signal remains untouched.
Step 6: Super Subs
Once you have your bass parts under control and playing nicely with everything else in your mix you might want to start considering ways to enhance their presence and depth. As we discussed in the previous step, you can use a simple EQ, but sometimes something with a little more poke may be needed.
A good area to look into is psycho acoustic bass enhancement. This process involves using some clever algorithms to improve the low end extension of a sound without increasing it's overall level or altering it's dynamic range. Clever stuff indeed but is it really that great?
The simple answer is yes, it really can be extremely useful but this sort of processing really has to be used very sparingly, take things too far and you can end up with more sub than signal and all your work fine tuning your low end mix can go out the window. So, go easy here and the results can be pretty rewarding.
Step 7: Layering Up
One last approach you might want to think about is layering sounds. It's a no frills technique that can work wonders with synth and drum parts and when it comes to adding extra depth and extension to your bottom end, it's something you can turn to on a regular basis.
Start by adding layers to any synth bass lines you maybe using. This is really very similar to adding an extra 'sub' oscillator within the synths internal engine but by adding a secondary instrument to produce a lower frequency you will gain a huge amount of control. Every aspect of the new layer is easily edited and compressed and processed in other ways.
So hopefully this will give you some ideas when it comes to mixing your low end and should at least get you thinking in the right way.